The desert rose (Adenium obesum) is a striking plant with succulent stems and deep red flowers. Native to the Sahel regions, south of the Sahara (from Mauritania and Senegal to Sudan), and tropical and subtropical eastern and southern Africa and Arabia. The Desert Rose is also known as Desert Azalea, Mock Azalea, Sabi Star, Impala Lily, and Kudu Lily.
Every part of these plants demands interest. The Desert Rose plant has dramatically swollen stems on older plants that resemble a bonsai tree. This succulent provides bright flowers and while not in bloom it has interesting tight clusters of narrow, green leaves.
However, there is an important consideration when growing this plant, particularly in the house. Its sap is poisonous and should never come into contact with children or pets. It is suggested that if you get sap on yourself while handling the plant, wash your hands immediately.
Light: Full sun. Perfect for a sunny window.
Water: Water during the summer and spring. Reduce water in the winter, but keep hydrated enough to retain its leaves.
Temperature: Keep at least 50 F at all times; if you keep temperatures of 60 F or higher during the winter, the plant may retain its leaves.
Soil: A well-drained succulent mix, (We recommend Miracle Grow) with an ideal pH around 6.0 (slightly acidic).
Fertilizer: Fertilize during spring and summer with controlled-release fertilizer or liquid fertilizer according to label directions.
Propagation is typically by seed. If your plant develops a seed pod, plant the seeds as soon as possible after the pod ripens, to maximize the chance of germination.
The fresher the seeds the better. If you don’t have a mature plant for harvesting seeds, ask your seed supplier about freshness before buying.
Some gardeners use a heat source to keep the containers at 80-85 F; otherwise, they should be kept as close as possible to that temperature range. Once the seeds germinate, the plants should be ready for moving to a pot in about a month.
The desert rose can be propagated from branch cuttings, but the plants often fail to develop the characteristic (and highly desired) bulbous stem.
When Do Desert Roses Bloom?
Desert roses typically bloom for several weeks throughout spring and summer. With proper care, some new and improved cultivars may bloom year round.
Again, be patient. Desert rose plants may not produce blooms for several months, but if the plant is healthy and growing conditions are right, it will eventually produce blooms.
Reasons for Desert Rose Plants Not Blooming
If you recently repotted your desert rose, it may go through a period of rebellion while it adjusts to its new environment. For a while, the plant will divert its energy into growing roots instead of producing blooms.
As a general rule, desert rose plants need repotting about every two years, preferably in mid-spring. Move the plant to a container just one size larger. Use a potting mix that drains well and is sure the container has a drainage hole in the bottom. To give the plant time to adjust, withhold water for a week or two after repotting.
Desert rose plants are drought tolerant and can live several weeks without irrigation. However, the plant needs a fair amount of water to produce blooms. Problems arise when the plant is allowed to stand in soggy soil or water.
Not only will the plant stops blooming, but poorly drained soil can easily cause the plant to rot and die. Water the plant regularly during spring and summer, then cut back when the plant is dormant during fall and winter. In the ground, desert rose prefers rich, slightly alkaline soil.
Desert rose requires plenty of sunlight, and lack of light may be the reason for desert rose plants not blooming. Place the plant where it receives at least five to six hours of sun per day and preferably even more.
Desert rose doesn’t require a lot of fertilizer, but regular feeding ensures the plant receives the nutrients it needs to produce blooms.
Feed an outdoor plant two or three times during spring and summer, using a balanced, water-soluble fertilizer.
Feed indoor Adeniums every week during spring and summer, using a water-soluble fertilizer diluted to half strength. To encourage flowering, it may also help to use a phosphorus-rich fertilizer or bone meal.
Repot as needed, preferably during the warm season. To repot a succulent, make sure the soil is dry before repotting, then gently remove the plant from the pot.
Knock away the old soil from the roots, making sure to remove any rotted or dead roots in the process.
Treat any cuts with a fungicide and antibacterial solution. Place the plant in its new pot and backfill with potting soil, spreading the roots out as you repot.
Leave the plant dry for a week or so, then begin to water lightly to reduce the risk of root rot.
Adenium belongs to the genera Apocynaceae, which is native to Africa, the Middle East, and Madagascar.
The desert rose (A. obesum) is the only Adenium found in wide cultivation.
It has been hybridized extensively to obtain different flower colors, including orange, white, striped and the traditional red.
These are not difficult plants to grow well, provided they get enough sunlight and warmth. Like all succulents, they cannot tolerate sitting in water. Use a specialized soil mix designed for succulents and cacti. We recommend Miricle Grow Cactus and Succulent Soil.
Cardioactive steroids and cardiac glycosides are found throughout the entire plant. Hongheloside A, D, E and F; digitalinum verum, somaline, digitalinum verum hexacetate, digitalis like glycosides.
Severe gastrointestinal upset, Vomiting, diarrhea, obvious abdominal pain, cardiac abnormalities, decreased body temperature, anorexia, and inactivity.
A species of flowering plant in the dogbane family, Adenium obesum has long been used as a poison. In Africa until the 1980s, various tribes would use the twigs, bark, and sap of the plant to produce a powerful toxin for hunting.
This was generally accomplished by pulverizing the twigs and bark into a putty, then boiling with water over an open fire until all that remained was a paste-like substance, which they would then dip their arrowheads into.
Surprisingly powerful, these poison arrows could bring down large game.
The plant was and still is an important component of traditional medicine. In Somalia, the roots are mashed then boiled in water to make nose drops for a stuffed up nose. In the Sahel, another decoction is used to treat venereal diseases and as a lotion to treat skin diseases and kill lice.
The latex of the plant is also used for tooth decay and as a disinfectant for septic wounds. In Kenya, the bark is used as an abortifacient and chewed as a primitive form of “plan B” to induce abortion.
The stems are also powdered and applied to livestock such as camels and cattle to kill skin parasites.
As stated above, Adenium obesum has been intentionally decocted to create poisons capable of bringing down large game. As such it should be considered deadly and animals should be prevented from having access to it. Author L.P.A.
Plant Resources of Tropical Africa, known by its acronym PROTA wrote the following in regards to the plants toxic and potentially beneficial effects on the body:
In Adenium obesum, the presence of some 30 cardiotoxic glycosides has been demonstrated, which act in a similar way as digitalis from Digitalis. Digitalis acts upon the Na+K+-ATPase enzyme that regulates the concentrations of Na+ and K+ ions in body cells and so also modifies the Ca++ concentration.
In low doses, it is used to treat congestive heart failure (CHF) and heart rhythm problems (atrial arrhythmias), but in high doses, it leads to systolic heart failure and death.
The ethanol extract of the roots slows down the growth of Bacillus subtilis, but has not shown activity against Pseudomonas aeruginosa, Staphylococcus aureus or Candida albida.
Extracts from the root have shown a cytotoxic effect against several carcinoma cell lines.
The aqueous stem bark extract is a potential acaricide as it shows high toxicity on all stadia of development of the ticks Amblyomma spp. and Boophilus spp.
How Bad Is It?
Although the plant is described as extremely distasteful and it is unlikely that a pet could tolerate consuming large quantities, it only takes a small amount to be lethal. Induce vomiting (the vomitus should be considered toxic and may result in additional intoxication and should be handled as a toxic substance).
Gastric Lavage to remove any undigested plant matter, Seek Emergency Veterinary Treatment. Medications to counteract the effect on the heart may be necessary. In many cases, even with prompt veterinary treatment, the animal will still die.
The roots and stems contain the same glycosides and in similar amounts. Oleandrigenin and some of the glycosides derived from it have cytotoxic effects and are being studied as potential components of anticancer drugs.